New Wireless Power Transmitters for Extended Transmission Distance and Enhanced Output Power

Opportunity

The global market for implantable medical devices was valued at about USD 105.7 billion in 2023 and is expected to grow to USD 207 billion by 2033 at a CAGR of 6.9%, highlighting the demand for high-efficiency wireless chargers in healthcare. Inductive wireless power transfer, which relies on magnetic fields, is the safest and most cost-effective method for powering implantable medical devices. However, conventional designs face weak coupling issues, leading to inefficiencies. 

The invention resolves these challenges by boosting wireless charging efficiency, enabling faster charging, smaller battery requirements and improved energy transfer. Beyond medical applications, the technology enhances wireless power transmission in drones, robotics, electric vehicles and underwater systems, offering a scalable, cost-effective solution for next-generation wireless energy transfer. 

Technology

The wireless power transfer technology incorporates a dual-coil system, consisting of a source coil and an amplifier coil. The source coil is a planar transmitter coil mounted on a truncated cone, while the amplifier coil, either planar or conical, is positioned below it to enhance power transfer efficiency. 

Figure 1: Coil structures of the wireless power transmitters with [Left] planar amplifier coil and [Right] conical amplifier coil. 

Both coils are compensated using LCC networks, where L denotes inductors and C denotes capacitors. This ensures their resonant frequencies align with the system frequency. The amplifier coils, tuned slightly above the system frequency, amplify energy transmission. 

Figure 2: Equivalent circuit of a typical wireless power transfer system with the invented transmitter.

Performance comparisons across multiple models demonstrate substantial output power and extended transmission distance. The conical amplifier coil design achieves the highest efficiency, surpassing conventional systems while remaining lighter than ferrite-based alternatives. 

Figure 3: Structures of the four models used for practical comparisons. 

Figure 4: Comparisons of the system output power with same transmission distance across the four models. 

Figure 5: Comparisons of the system transmission distance with same output power across the four models.

Figure 6: Comparisons of the weights among the [Left] ferrite, [Middle] planar amplifier coil, and [Right] conical amplifier coil. 

Applications & Advantages

Applications: 

• Electrical vehicles 
• Robotics and drones
• Medical devices
• Underwater vehicles 

Advantages: 

• Higher output power for high-efficiency wireless chargers.
• Extended transmission range for long-distance wireless charging.
• Cost-effective alternative to traditional charging methods.
• Lightweight design, which improves portability and integration.